As an example of processes of manufacturing a semiconductor device, a process of forming a film on a substrate is often carried out by supplying a processing gas to the substrate in a process chamber.
In some cases, when performing the aforementioned film forming process, deposits are attached onto members in the process chamber as well as a substrate. The deposits may cause particles (e.g., foreign materials) in the process chamber and thus become one of the factors for reducing the quality of the film forming process.